Telegraphic transmitter



Feb. 21, 1939. H. MARTIIN, m 2,l48,0

TELEGRAPHIC TRANSMITTER Filed Nov. 2, 1957 2 Sheets-Sheet 1 INVENTOB i fl [ATTORNEY Feb. 21, 1939. H. ;e. MARTINI, JR 2,1489% TELEGRAPHIC TRANSMITTER Filed Npv. 2;.193'7 V 2 Sheets-Sheet 2 WWW/wad ATTORNEY Patented Feb. 21, 1939 PATENT OFFICE TELEGRAPHIO TRANSMITTER Horace G. Martin,

In, Brooklyn, N. Y.

Application November 2, 1937, Serial No. 172,365

3 Claims.

This invention relates to telegraphic apparatus for transmitting messages in the form of dash and dot and commonly known as the Morse code.

The ordinary Morse key requires a movement 5 of the hand, not only for each dash but also for each dot. This is extremely tiresome and wearing on the muscles and nerves of the operator, as the dots predominate in the Morse code. Devices having vibrators have been introduced having certain vibratory mechanism whereby the key requires only two movements, one of which causes the usual dash, and the other of which automatically produces a series of the dots. While with such devices there has been some relief on the nerves of the operator, the same have the drawback that they always necessitate the starting of a series of vibrations for each letter or numeral. This repeated starting of the vibrations is objectionable because of the effort necessary to overcome the natural tendency of the vibrator to lag when the key is thrown over to produce the desired series of vibrations.

Moreover, to produce just that series of vibrations that will result in the desired number of dots by the throw of the key requires a certain adjustment according to the special touch and skill of the operator. As a result of such individual adjustment the instrument can be used only by the particular operator, and anew adjustment would be necessary for any other oprator. Not only that, but if the particular operator is called upon to transmit a message from a different position in the operating room than that usually occupied by him, he is obliged to bodily carry his own instrument over to the new position, which entails loss of time due to the necessity of disconnecting and connecting the apparatus.

Furthermore each instrument of the known type generally includes the vibrator and adjusting mechanism, as a unit which render the same relatively expensive.

The main object of this invention, therefore, is to provide an improvement which will not only simplify the construction of the transmitting apparatus but also its operation, so that its dependency on individual skill and touch will be considerably lessened, if not entirely eliminated.

Another object of my invention is to provide a construction that will reduce the cost of production of the individual key lever mechanism.

A further object is to provide an apparatus in which the dot making instrument can be constructed as a separate unit from the key portion thereof, so that it may be mounted at some distance away from the operator's seat and serve as a master unit for as many operators as is desired. With such construction the instrument to be used by an individual operator will consist merely of the key operated dash producing contacts and a second contact to close and openthe electrical connection with the contact of the dot making instrument.

To accomplish my objects I provide the usual key lever mechanism with the dash making contacts and a spring contact for the dot making transmitter, which consists of a contact member adapted to be in continuous uniform motion, so that when the key is thrown in the direction to produce dots, its corresponding contacts will cause the alternate closing and opening of the electrical circuit through the said constantly moving contact member, producing the number of impulses or dots according to the length of time the key lever is held in the position into which it was thrown. Special adjustment on the key operated element to conform with individual touch or skill is eliminated.

In practice the constantly moving dot making mechanism may consist, for instance, of a motor or otherwise impelled rotor having a series of equi-distantly spaced contacts with which the key operated contact when thrown into the path of said rotor will cooperate and produce a series of dot forming impulses.

This constantly moving device may be either applied to and form a unit with the key portion of the apparatus or be constructed as a separate unit to be mounted at any suitable distance from the operating place and capable of serving as a master transmitter for a number of operators simultaneously.

My invention consists in the novel combination, arrangement and construction of parts as will be hereinafter more fully described and defined in the appended claims:

Figure l is a plan view of one embodiment of my novel transmitter;

Figure 2 is cross section of Figure 1 on line 2-2 of Figure I seen in the direction of the arrows;

Figure 3 is a longitudinal section on line 3--3 of Figure I seen in the direction of the arrows;

Figure 4 is a top plan view of a modified construction of my transmitter; and

Figure 5 is a diagrammatic View of another modification thereof.

Referring more in detail to the drawings, l0 denotes a base which may be made of iron or other suitable material provided with insulating feet |2 denotes a frame or standard projecting upwardly from and fixed to the base and through which extends a key lever 3. The latter is carried by a member 4 which is mounted on a vertical pivot l5, working in suitable upper and lower bearing screws (not shown) so that the key lever l3 can be swung horizontally in either direction. l6 and I! denote stops carried by horizontal arms |8, I9 projecting longitudinally from the frame l2. A spring adjustably mounted between the arm l8 and the key lever l3 tends to normally hold the latter in contact with stop I 1. The member I4 is extended outwardly in longitudinal direction of the key lever l3 and constitutes part thereof, carrying at its free end the insulated thumb 2| and finger piece 22 suitably attached thereto. This extended part M of the key lever has, as hertofore stated, a. vertical pivot connection with the main part l3 of the key lever and is yieldingly held fiat against the latter by an adjustable spring 23 mounted around a screw 24 projecting from the lever l3 and bearing an adjusting nut. 25 denotes an adjustable horizontally extending screw contact projecting through a post into the path of a contact point 26 fixed to the part M of the key lever. When the key lever through the thumb and finger pieces 2|, 22 is swung to the left from its normal position, shown in Figure 1, the main part l3 of the lever will remain stationary against the stop l7, while the part l4 thereof will swing on its pivot |5 against the tension of spring 23 until its contact point 26 strikes the contact 25. Thereby the circuit will be closed and remain closed as long as contact 26 is held in engagement with the contact 25, thus transmitting a prolonged impulse or dash of corresponding duration.

2! denotes a manual switch lever, pivoted to the base at 2'! and formed at one end with an operating knob 28. The other end of said switch lever is adapted to slip under and in close contact with a clip 29 extending from the post 30. The external circuit is connected to binding posts SI, 32, the post 3| being in electrical connection with the base l0 and hence with the key lever l3 through the standard l2 and pivot l5 while the binding post 32 is connected through conductor 34 with an insulated post 35. The inner end of the key lever has attached to it a U-shaped spring 36, carrying a contact point 31 forming part of the dot transmitter.

Thus far the construction is well known. In the known instruments the contact point for the transmission of dots" is carried by a vibrator attached to the key lever and adapted to cooperate with a stationary contact.

In contradistinction to such construction, which is objectionable because of the drawbacks heretofore stated, my device employs a continuously moving contact element with which the contact 31 of the key lever is adapted to cooperate.

According to the construction shown in Figures 1 to 3 this moving contact element consists of a disk or drum 38 mounted on a shaft 39 rotatively supported in bearings 40 and impelled from an electric motor 4|. This motor may be mounted on or near the base and motion of its shaft 42 may be transmitted to the shaft 39 through a worm gear mechanism 43, 44 or by other suitable means. The motor may be driven through an electric source such as battery (not shown). The disk or drum 38 on its circumference may be provided with a series of equidisand is arranged to the contact 31. The

, motor may be set in motion when the operator takes his seat at his instrument and the rotor thus kept running continuously with uniform speed.

It will be obvious, that by the use of a continuously revolving contact rotor with uniform speed and on which a series of contact points are equidistantly distributed the operation of the instrument for the transmission of dots becomes greatly simplified, considerably lessening the nervous strain on the operator. Not only that, but it provides a more musical or symphonious tone quality than by the hitherto used instruments and lessens skippy transmission which is produced in the old instruments due to improper individual adjustments. In lieu of a rotor, any other suitable constantly moving contact element may be employed.

Thus according to Figure 4, a constantly impelled vibrating element is used. This vibrator may be actuated by an electro-magnet 45 or other suitable means and comprises a bar or rod 46 which by a. leaf spring 41 is fixed at one end to a grounded post 48. At its opposite end it may carry a weight 49 for the adjustment of the frequency of vibrations. It also carries a spring contact 50 adapted to cooperate with a stationary adjustable contact 5|. The key lever l3 which is constructed and operated similar to the key lever l3 of the first modification, at its free end is adapted to bear against one of a pair of contact arms 52, 53 insulated from one another and whose contact points 52, 53 are normally separated, but which are brought into contact by swinging the key lever Hi from its right hand position, where it bears against stop to the left hand position where it will bear against stop Hi. In this position it is held so long until the desired number of impulses or dots are produced by the continuously vibrating contact 50 and stationary contact 5| cooperating therewith.

The electro-magnet 45 may be energized through a battery circuit A or other electric source, and is adapted to cause the bar 46 to constantly vibrate so that its contact 50 in cooperation with the stationary contact 5| will continuously and alternately close and open.

When the key lever I3 to close the contacts 52, 53' of the arms 52, 53 the line circuit to the receiver (R) and through the contact 5| will be closed, so that a number of impulses or dots will be transmitted, the number of which depends upon the length of time the key lever I3 is retained in its left hand or operative position.

In the two modifications hereinabove described the rotor and the vibrator and their operating means have been shown as applied to the base of the instrument and constituting a unit with a key lever instrument. This,0f course, is not a requirement. In fact the instrument can be greatly simplified by separating the rotor or vibrator and the operating means thereof from the key lever mechanism, and by mounting the rotor or vibrator and the operating means thereof at some suitable place in the operating room away from the key lever mechanism. In such a case the rotor or vibrator may be used as a master transmitter.

This is shown in Figure 5. Here the dot transmitter which, as shown, may be in the form of a constantly revolving rotor 54 of a similar is thrown to the left construction to that shown in the first modification, is not a part of the key lever unit, but may be mounted at any suitable place of the operating room and be impelled by any suitable driving means, from an electric motor 4|, as in Figure 1. Cooperating with said rotor is a single take off contact member continuously bearing against the contact face of said rotor.

Each key lever instrument comprises a base III on which is pivotally mounted the key lever I3 of similar construction as in the first modiflcation and which is adapted, when thrown to the left to close its dash producing contacts and when thrown to the right, to bring its spring contact 31 to bear against a stationary adjustable contact 55. In this position the key lever I3 is retained until the desired number of dot signals have been produced.

The electricconnections here are as follows:

One pole of an electric source B is grounded and the other pole is connected to the stationary contact 30 of each unit for the dash producing pair of contacts. Said other pole is also connected to the rotor 54 and through the arm 55 which is continuously in contact with said rotor 54 is continuously electrically connected to the adjustable contact member 55 of each pair of dot producing contacts 56, 51 of each unit. The outgoing line of the two circuits is indicated by a wire 50 leading from the post 5| of each unit, which post is conductively connected by wire 62 to the key lever l3 through its frame I2.

Thus the units to be used by individual operators are of very simple construction and the cost of production considerably lessened. Any number of such units may be made to cooperate with the common transmitter 54 without any interference. They need no adjusting means to conform with individual touch or skill, since the rotor or vibrator is adapted to rotate continuously with uniform speed.

While I have described and shown the dot transmitter in form of a continuously rotating rotor or continuously vibrating element, it is obvious that without departing from the principle of my invention any other suitable continuously moving contact element may be employed to produce the desired eflect, namely, the automatic production of a series of impulses in transmitting dots", by a single throw and retention of the key lever in the dot making position until the desired number of "dots have been produced and without the necessity of starting and stopping the moving contact element for each letter or number to be transmitted, as with the hitherto known devices.

What I claim is:

1. In a telegraphic transmitting apparatus, the combination of a plurality of key lever units, each comprising a stationary contact, a contact on said lever, an electric circuit adapted to be closed when said key lever is moved in a certain direction to cooperate with said stationary contact to produce a dash, another pair of contacts for the transmission of "dots, one being stationary and the other also on each of said key levers, a constantly impelled electric element capable of acting continuously as a source of dot signals and serving as master transmitter for all said units, said master transmitter being remote and separate from said key lever units. and electric connections between said second named stationary contact of each key lever and said constantly impelled master transmitter, whereby a series of impulses or dots will be produced when any of said key levers is moved into the opposite position to that of the "dash making position to close the circuit and is retained in that position until the desired number of impulses is produced.

2. In a telegraph transmitting apparatus, a portable key lever unit comprising two pairs of contact members, one pair for the dash signals and another pair for dot signals, a nonportable constantly impelled means capable of acting continuously as a source of dot signals, and electric circuits, one controlled by one pair ofcontacts to produce a dash and another controlled by said non-portable means and said '5 other pair of contacts to produce dots".

3. In a telegraph transmitting apparatus, the combination of a plurality of portable key lever units, each comprising two pair of contact members, one pair for producing a dash and another pair for producing "dots, a non-portable means capable of acting continuously as a source of dot signals, and electric circuits, one controlled by one pair of contacts of each unit to produce a dash when the key lever of any one of said units is shown in one direction and the other controlled by said common means and the other pair of contacts to produce dots when said key lever is thrown in opposite direction, said non-portable means being common to and separate from said key lever units.

HORACE G. MARTIN, J R. 

